lecture 36 - outbreaks Flashcards
what is the one health approach
the interaction and intersection of humans and animals both domestic and wild and the environment including climate change
what is included in the epidemiological triangle
- what (agent)
- who (person/population)
- where (place)
- when (time)
- why/how (causes, risk factors and modes of transmission)
what are examples of infectious agents
bacteria, viruses, fungi, protozoa
what is infection
entry of a microbiological agent into a higher order host and its manipulation within the host
what is infestation
external surface only (e,g lice and scabies)
what is infectivity
ability of an organism to invade and multiply in a host (secondary attack)
what is pathogenicity
ability of an organism to produce clinical symptoms and illness (proportion of those exposed who get ill)
what is virulence
ability of an organism to produce serious disease (case-fatality rate)
what is direct transmission
touching or inhaling infectious secretions (salvia, respiratory droplets, urine, feces, other bodily fluids)
what is indirect transmission and the two types
always involves a vehicle
- inanimate = food or water, soil, fomites (bedding, clothing, utensils)
- live = vector (mosquitos, ticks)
what is airborne transmission
- droplet nuclei, small particles
what is an outbreak / epidemic
unexpected increase in the incidence of a disease
- occurrence of cases in excess of those expected
what is an endemic
constant presence of a disease or infectious agent within a geographical area or population group
- e.g malaria endemic to parts of africa
what is holoendemic
intense disease all year round
- children mainly infected, most adults immune
what is hyperendemic
intense disease with time periods of no transmission e,g during the dry season
- persistant disease with all ages infected
